Foul smelling gases in the air are treated by the adsorption method using activated carbon, the masking method using other scents, the chemical method for effecting a chemical reaction with, for example, the odorous substances, so as to eliminate or reduce the foul smelling or unpleasant smelling substances. The adsorption method using activated carbon, however, has the problem of degradation of the deodorizing capability in a short time period. Further, since the activated carbon is flammable, there is the disadvantage of its easily becoming a causative factor in fires. In the masking method using other scents, the scents sometimes cause new unpleasantness, and therefore, this cannot be said to be a fundamental solution to the problem. In the chemical method for removal of the foul smelling or unpleasant smelling substances by chemical reactions, there is known, for example, the method of oxidation and decomposition of foul smelling gaseous substances by, for example, ozone, but excessive ozone is harmful to human health, and therefore, there is the problem that a new type of harm is caused. That is, since it is difficult to control the amount of the chemical substance for reacting stoichiometrically with the foul smelling gaseous substance, an unnecessary chemical substance remains and thus this is, again, not a fundamental solution to the problem.
For example, it is difficult to remove acetaldehyde, the main odorous component in cigarette smoke, even using activated carbon. For this purpose, various measures have been taken, such as the improvement of the removal capability by adding the highly chemically reactive aniline to activated carbon, as described in Japanese Unexamined Patent Publication (Kokai) No. 56-53744, and removal by effecting a chemical reaction with phenylhydrazine, as described in Japanese Unexamined Patent Publication (Kokai) No. 56-95319. However, according to the discoveries of the present inventors, the foul smelling odor of the chemically reactive substance itself becomes a problem or the maintenance of the activity of the chemical substance is difficult and the usage life is short. Therefore, these are not fundamental solutions either.
The present inventors previously invented a deodorant composition superior in speed of removal of foul smelling substances such as the four major foul smelling substances of ammonia, trimethylamine, hydrogen sulfide (H.sub.2 S), and methylmercaptan (CH.sub.3 SH) and superior in life and proposed the same in Japanese Patent Application No. 3-188939. This uses the reaction product produced by causing contact of, for example, ascorbic acid with a metal such as iron or manganese in a state in the presence of unreacted iron, manganese, etc. This composition can be inexpensively manufactured and features extremely small degradation of the air purifying power with the elapse of time, and therefore, was an improvement over the prior art, but the capability in the removal of aldehyde was of a level requiring further improvement for practical application. In particular, in industry, development of a deodorant which exhibits improved speed of removal of acetaldehyde, formaldehyde, trimethylamine, and ammonia and sustained performance over a long period has been desired.